Cyclopentanophenanthrene compounds



United States Patent 3,107,240 CYCLOPENTANOPHENANTHRENE COMPOUNDS Howard J. Ringold, Shrewsbury, Mass., and George Rosenkranz, Mexico City, Mexico, assignors to Syntex Corporation, Panama, Panama, a corporation of Panama No Drawing. Original application June 8, 1960, Ser. No. 34,633. Divided and this application July 26, 1962, Ser. No. 212,736

Claims priority, application Mexico Apr. 24, 1958 19 Claims. (Cl. 260-23955) The present invention relates to novel cyclopentanophenanthrene derivatives.

In particular the invention relates to A -pregnene-16a, 17a-diol-3,20-diones halogenated at C-6 with a chlorine or fluorine atom and which may also have an additional double bond between 0-1 and C2 and/or a hydroxy group at C-2l, as well as to esters thereof.

The present application is a continuation-in-part of our copending applications Serial No. 807,774, filed on April 21, 1959, and of Serial No. 56, filed on January 4, 1960, now abandoned, and a division of Serial No. 34,633, filed on June 8, 1960.

The novel compounds of the present invention which are progestational agents of anti-estrogenic efl ect are illustrated by the [following formulas:

Y ph 03g c'rno R3 In the above formulas, X represents chlorine or fluorine; Y represents a double bond between C-1 and 0-2 or a saturated linkage between 0-1 and C-2; R represents hydrogen, hydroxy or an acyloxy group of a hydrocarbon carboxylic acid of up to 12 carbon atoms; R R and R each represents hydrogen or an acyl group of a hydrocarbon carboxylic acid of up to 12 carbon atoms; and R and R represent hydrogen or lower alkyl.

The novel compounds of this invention are also valuable intermediates for the preparation of 6cz-fll101O-l6ochydroxy cortical hormones since an oxygen function can be introduced at (3-11 by known biochemical methods to form compounds having anti-inflammatory activity. For example, the incubation of 6a-fluoro-A -pregnene- 160:,17u-21-triol-3,20-dione and of 6a-fiuoro-A -pregnadiene-16a,l7a,21-triol-3,20-dione with suprarenal glands of bovine or with species of Czmninghamella baz'nieri ATCC 9244 effects introduction of the hydroxyl group in the fi-position at C-ll whereas incubation with Rhizopus 3,107,240 Patented Oct. 15, 1963 m'gricans ATCC 6227b produces hydroxylation in the a-position. Similarly, the 16,17-acetonide of 6wfluoro- M-pregnened6a,17a,2l-triol-3,20-dione or the l-dehydroderivative thereof can be incubated to introduce llfl or llmhydroxy groups. Thus, 6a-fl1101'O-16cx-hYdI'OXY-hY- drocortisone, 6oz fluoro-l 6u-hydroxy prednisolone and their 16,17-acetonides as well as the ll-epi compounds are produced from the novel compounds of this invention.

The ll-hydroxyl group of the aforementioned compounds can be oxidized to the keto group, for example by reaction with chromic acid in dilute acetic acid with previous protection of the other hydroxyl groups which may be attacked during the oxidation. The 16,21-diesters of 6a-fluoro-l6a-hydroxy-hydrocortisone and of 6a-fluoro- 16u-hydroxy-prednisolone are converted into the respective diesters of Ga-fiIIOI'O-IGa-hYdI'OXY cortisone and of 6a-fluoro1'6whydroxy-prednisone. For the oxidation of the lla-hydroxyl group one starts from a 21-ester of the 16,17-acetonide of 6rx-fluoro-l6a-hydroxy-hydrocortisome or from a 21-ester of the 16,17-acetonide of 6afluoro-l6a-hydroxy-prednisolone.

Furthermore, the 6a-fluoro-11-hydroxy derivatives of A -pregnene-l6a,l7a,2l-triol-3,20-dione and of its l-dehydro analog can be dehydrated at C-9,11 with previous protection of the other primary and secondary hydroxyl groups, for example, they are heated with methanesulfonyl chloride in mixture with dirnethylforrnarnide and pyridine, to produce the 16,21-diesters of ova-fluoro- A -pregnadiene-Ma,17a,21-triol-3,20-dione and of its l-dehydro analog as well as the 21-esters of the 16,17- acetonides of the latter, respectively. Such compounds are valuable intermediates for the preparation of 60afluoro-9a-halo-16a-hydroxy cortical hormones, since there can be applied the method of Fried et a1. [1. Am. Chem. Soc., 79, 1130 (1957)].

The novel compounds of the present invention where R is hydrogen or acyloxy and R and R are acyl, are partioularly useful progestational agents.

The new compounds may be prepared in the following manner. The preparation of the novel compounds wherein R and R represent acyl groups and R and X represent the same groups as heretofore stated, may be illustrated by the following equation:

CHaR

CHnR I fluoro pregnane 5a,l6a,l7a,21 tetrol 3,20 dione (III; R=acyloxy), respectively. Dehydration by means of a reaction with a strong enough acid caused the regeneration of the A -double bond. The dehydration may be accompanied by the inversion of the steric configuration at C-6. For example, a shout treatment with concentrated aqueous hydrochloric acid in acetic acid solution produced the corresponding diester of 65-fiuoro-A -pregnene-16a,17a=diol-3,20-dione (IV: X=F; R=H) or the corresponding triester of 6B-fluoro-A -pregnene-16a,17a, 21-triol-3,20-dio ne (IV; X=flF; R=acyloxy). The treatment with dry hydrogen chloride in glacial acetic acid solution caused also the simultaneous inversion of the steric configuration at C6 and thus we obtained the 6a-fluoro-analogs of such compounds (X=ocF).

For the introduction of a chlorine atom at C-6 of the diester of 16a,17u-dihydroxy-progesterone or of the triester of the l6a-hydroxy analog of compound S, we converted such compounds into their S-aIkyl-enol-ethers, preferably into their B-ethyl-enol-ethers (V: R=H or acyloxy) and these compounds we treated with hypochlorous acid, using any reagent capable of liberating such acid, such as an N-chloro amide or imide or the hypochlorite of an alkali or alkali-earth metal. For example, we employed N-chlorosuccinimide in mixture with acetone, sodium acetate and acetic acid. Thus we ob tained a diester of 6,8-chloro-A -pregnene-16,17a-di0l- 3,20-dione (IV: X=BC1; R=H) or a triester oi 6,8-chloro-A -pregnene-16a,l7u,21-triol3,20-dione (IV: X={3Cl; R=acyloxy). The aforementioned treatment with dry hydrogen chloride in glacial acetic acid aiforded the 60:- isomers of such compounds.

The dehydrogenation between 0-1 and C-2 can be carried out by known purely chemical methods or microbiological methods. Preferably we refluxed a compound of Formula IV with selenium dioxide, in the presence of pyridine and in mixture with t-butanol, under an atmosphere of nitrogen. Thus we obtained a diester of the and 6 3-isomers of the corresponding 6-halo-A -pregnadiene-16a,17a-diol-3,20-dione (VI: R=H) or a triester of the respective -halo-n' -pregnadiene-16a,17a,21-trioldiester of 3-ethylenedioXy-5u,6o-oxido-pregnanel60:,1711- diol-20-one ('II; R=H) or the corresponding u'iester of 3-6I'i'1Yl6I1CdlOXY-5a,6oc oxido pregnane l6oc,17o,21-tfi0l- 20-one (II; R=acyloxy). By subsequent reaction with boron trifluor-ide etherate, preferably in mixture with benzene and ether, at room temperature, we opened the epoXide ring with the addition of the elementsof hydrogen fluoride, and then we hydrolyzed the ketal group, for example by treatmentwith p-toluenesulfonic acid in acetone solution at room temperature. Thus We produced a 16,17-diester of 6(3-fiuoro-pregnane-5a,l60:,17atriol-3,20-dione (III; R=H) or a 16,17,21-triester of 3,20-dione (VI: R=acyloxy) The ester groups can be formed with radicals of carboxylic acids having up to 12 carbon atoms, saturated or unsaturated, of straight or 'branched chain, cyclic or mixed cyclic-aliphatic, substituted or not by methoxy, halogen or other groups, and include such esters as the acetates,

CHnOAG o le 0% CHaOAC CHzOR' WIS CHzOAO OHzOAO XVI CH2OA0 In the above formulas Y represents a double bond between C-1 and 0-2 or a saturated linkage between C-1' and C-2. Ac represents the acyl group of a hydrocarbon carboxylic acid of up to 12 carbon atoms.v

The known starting material 16u,17a-oxido-A -pregnew-313,2l-diol--one-21-acetate described by Julian et al., I. Am. Chem. Soc., 72, 5145 (1950), is reacted with chromous chloride according to the method of Julian and Cole, J. Org. Chem., 19, 131 (1954), to form the known A -pregnadier1e-3fl,2l-diol-2O-one121acetate. The latter is hydroxylated by the procedure described by Petrow et al., J. Am. Chem. Soc., 4373 (1955), with potassium permanganate to produce A -pregnene-3fi,16a,17a,2ltetrol-ZO-one Zleacetate which is transformed into the 16,17-cyc1ic ketalor acetal by reaction with a ketone such as acetone or an aldehyde in the presence of catalytic amounts of perchloric acid to protect the 16,17-dihydroxy grouping. For introduction of the 6-fluoro moiety, the aforementioned 16,17-acetonide is epoxidized by treatment with conventional reagents such as a peracid, for example, monoperphthalic acid, followed by chromatog- 7 e=o 7 C 0 CHs no F raphy of the crude product. The resulting l6a,'17u-isoprbpylidenedioxy-Zl-acetoxy 5a,6oz oxido-pregnan-3fiol-20-one is treated with boron trifluoride etherate, pref erably inmixture with benzene and ether, at room temperature to open the epoxide ring and introduce the elements of hydrogen and fluorine to form 6/"3-fil101O-16a, l7a-isopropylidenedioxy 2l acetoXy-pregnane-3fl,5adiol-ZO-one which upon oxidation with an oxidizing agent such as chromic acid in dilute sulfuric acid yields the corresponding 3-keto compound. Upon treatment of the last mentioned compound with dry hydrogen chloride in acetone, dehydration accompanied by inversion of the steric configuration at (3-6 is effected to produce 6ot-fii1OI0-16a, 17u-isopropy1idenedioXy-2l-acetoXy A pregnene-3,2Q- dione.

The dehydrogenation between 0-1 and C-2 can be carried out as mentioned previously by known chemical methods ormicrobiological methods to form Get-fluoro- 1'6a,17m-isopropylidenedioxy 21 acetoxy-A -pregnadiene-3,20-dione.

, The 16u,17o;-dihydroxy grouping is regenerated by hydrolysis of the l6a,17a-ketal by treatment of the latter with 60% formic acid under reflux conditions thus yielding 60: fluoro A pregnene-l6a,17a,21-triol-3,20-dione, 2l-acetate or the 1-dehydro compound respectively. Further treatment with dilute alkaline solution, such as potassium hydroxide, results in saponification of the 2l-acyi group to form the 6a-fluoro-A -pregnene-16a,1704,21- triol-3,20-dione or the l-dehydro form.

In another aspect of this invention, the 6u-fiuoro-A pregnene 16cc,170:,2l-t1iOl-3,ZO-diOIlG-Zl-SJCfi'EHIG obtained above can be treated with acetic anhydride in pyridine to produce the il6a,21-diacetate. Either the 21-monoace-tate or the 16a,21-diacetate is dehydrogenated with selenium dioxide to yield the corresponding 6a-fiuoro-A -pregnadiene-16a,l7oc,21-triol-3,ZO-dione-Zl-acetate or the 16,21- diacetate. Treatment of the latter with dilute methanolic alkaline solution results in the free 6wfluoro-A pregnadiene-16u,17u,21-triol-3,20-dione which can further be reesterified by conventional means.

The blocking of the 16a,17a-dihydroxy-20-keto grouping by ketal formation is necessary prior to the fluorination step to avoid formation of D-homo compounds. Thus in the general method of preparing 6a-fiuoro-16a, 17u-dihydroxy steroids, ketalization or acetalization of the l6a,17a-dihydroxy grouping is carried out prior to opening the 50,6oc-6POXid6 to introduce the elements of hydrogen fluoride. Thus, for example, the 16 x,17a-isopropylidenedioxy-Zl-acetoxy-A -pregnene 3,20 dione of Petr-ow et al., J. Chem. Soc., 4387 (1955), can be converted into the 3-cycloethyleneketal, followed by epoxidation of the double bond which is shifted between -5 and C6, and then subsequent treatment with boron trifluoride yields 65 fluoro 3 ethylenedioxyl6u,17oc-isopropylidenedioxy-2l-acetoxy-pregnan-5a-ol-20-one. Hy-

' drolysis of the 3-keta1 group, followed by dehydration at C-5 causes regeneration of the A -3-keto group and inversion of the steric configuration at C-6; further hydrolysis of the 16a,17a-isopropylidenedioxy group affords the V 6u-fiuoro-A -pregnene-16a,17a,21-triol-3,20-dione. Similar treatment of the 16e,17a-acetonide of the 21-acetate of 3-ethylenedioxy-A -pregnene 16a hydroxy cortisone and of the acetonide of 21-acetate of a 9oa-halo-16a-hydroxy-hydrocortisone results in the 21-acetate of 60:- fiuoro-16a-hydroxy cortisone and 6ufl11OI'O-9oL-halO-16ohydroxy-hydrocortisone The following preparations illustrate the production of starting compounds.

PREPARATION 1 Similarly, A -pregnene-16a,17u,21-triol-3,20-dione or the 21-monoacetate thereof was converted into its tri acetate.

PREPARATION 3 When in the method of Preparation 1, the acetic anhydride was substituted by the anhydride of another carboxylic acid having up to 12 carbonatoms, there were obtained, from A -pregnene-16u,17a-diol-3,2O-dionethe corresponding diesters, and from A -pregnene-16a,l7a, 2l-triol-3,20-dione or the 21-monoacetate thereof the respective triesters. onic anhydride there were prepared the propionates, and

reaction with caproic anhydride gave the Jcaproates.

When a long chain anhydride was used the reaction time was extended to 4 days.

PREPARATION 4 5 g. of A -pregnene-16a,17a-diol-3,20-dione dissolved in cc. of pyridine was treated with 5 cc. of propionic anhydride and kept overnight at room temperature; the mixture was poured into ice Water, heated for half an hour on the steam bath, cooled and the precipitate was collected, washed with water, dried and recrystallized from acetone-hexane, thus giving A -pregnene-16a,17udiol-3,20-dione 16-propionate.

By subsequent treatment with cyclopentylpropiom'c acid anhydride, in accordance with the methods described in the previous preparations, there was obtained the 16- propionate-l7-cyclopenylpropionate of A -pregnene-16a,

' 17oc-diol-3,20-dione.

PREPARATION 5 triol-3,20-dione, respectively.

The following specific examples serve to illustrate but are not intended to limit the present invention.

Example I A mixture of 5 g. of A -pregnene-16a,17a-diol-3,2O-

dione-diacetate, 300 cc. of anhydrous benzene, cc. of ethyleneglycol and 250 mg. of p-toluenesulfonic acid was refluxed for 12 hours with the use of an adapter for the Forexample, by reaction with propicontinuous removal of the water formed during the reaction; 50 cc. of 5% aqueous sodium carbonate solution and'500 cc. of water were added to the cooled mixture and the benzene layer was separated, washed with water, dried over anhydrous sodium sulfate and evaporated. The residue consisted of the crude 3-ethylenedioxy-A pregnene-lfia,l7a-diol-20-one diacetate, which was used for the next step without further purification. In another experiment this compound was purified by recrystallization from acetone-hexane.

A cooled solution of 5 g. of the above ketal in cc. of chloroform was mixed'with an ether solution of monoperphthalic acid containing 1.2 molar equivalents of the reagentjthe' mixture was'kept at 0-5 C. for 16'-'hours in the dark and then diluted with water; the' organic'layer was separated, washed with water, dried over anhydrous sodium sulfate, evaporated to dryness and purified by chromatography. There was thus obtained 3-ethylenedioxy- 5a,6a-oxido-pregnane-l6a,17a-diol-20-one diacetate.

A solution of 3 g. of the above compound in a mixture of cc. of ether and 150 cc. of benzene was treated with 3 cc. of boron trifluoride etherate and the mixture was kept at room temperature for 3 hours and then diluted with water; the organic layer, dried over anhydrous sodium sulfate was evaporated to dryness' The residue was purified by chromatography on neutral alumina to give 6fi-fluoro-3-ethylenedioxy-pregnane-5a,16a,17a-triol- 20-one16,17-diacetate.'

A solution of 2 g. of the above ketal in 150 cc. of ace-' 9 With water, dried and purified by recrystallization from acetone. There was thus obtained 6l3-fluoro-pregnane- :1,16a,17a-trio1-3,2O-dione-16,17-diacetate.

A solution of 2 g. of the above compound in 100 cc. of acetic acid was mixed with 2 cc. of aqueous concentrated hydrochloric acid and the mixture was kept for 1 hour at room temperature, diluted with water and the precipitate formed was collected, washed with water, dried and recrystallized from acetone-hexane, thus giving 6fi-fluoro-A -pregnene-l6a,l7a-diol-3,20-dione diacetate.

A mixture of 2 g. of the above compound, 100 cc. of anhydrous t-butanol, 0.8 g. of selenium dioxide and 0.5 cc. of pyridine was refluxed under nitrogen for 72 hours, cooled, filtered through celite washing the filter with a little hot t-butanol, and the filtrate and washings were combined and distilled to dryness under reduced pressure. The residue was dissolved in acetone, treated with decolorizing charcoal under reflux, cooled, dried over anhydrous sodium sulfate and evaporated to dryness. Chromatography of the residue on neutral alumina yielded GB-fluoro-A -pregnadiene-l6a,l7a-diol-3,2O-dione diacetate.

Example 11 By the method described in the previous example, A pregnenel6a,17a,21-triol-3,20-dione 16,17,21-triacetate was ketalized and then epoxidized to form 3-ethylenedioxy 5a,6a-oxido-pregnan-16a,17a,21-triol-20-one triacetate; through the reactions with boron trifiuoride and then with p-toluenesulfonic acid, the latter compound was converted into 6B-fluoropregnane-5u,l6oz,17a,21-tetrol- 3,20-dione 16,17,21-triacetate. Upon subsequent dehydration by treatment with aqueous concentrated hydrochloric acid, there was obtained 6,8-fluoro-A -pregnenel6a,17u,2l-triol-3,20-dione triacetate, which was dehydrogenated by refluxing with selenium dioxide. There was thus obtained 6,6-fluoro-A -pregnadiene-l6a,l7a,21- t-riol-3,20-dione triacetate.

Example III 1.5 g. of 6fi-fluoro-pregnane-5a,l6a,l7a-triol-3,20-dione 16,17-diacetate, intermediate in the method of Example I, was dissolved in 75 cc. of glacial acetic acid and a slow stream of dry hydrogen chloride was introduced into the solution for 2 hours while the temperature of the mixture was maintained below C. After pouring into ice Water the precipitate was collected, washed with water, dried and recrystallized from acetone-hexane. There was thus obtained 6a-fluoro-A -pregnene-160:,17adiol-3,20-dione diacetate, which was in turn refluxed with selenium dioxide to form 6a-fiuoro-A -pregnadiene-16a, 17a-diol-3,20-dione diacetate.

Example IV By an analogous method to that described in the previous example, 6B-iluoro-pregnaue-5a,l6a,17a,21-tetrol- 3,ZO-dione-l6,17,2l-triacetate, an intermediate in the method of Example II, was converted into 6a-fluoro-A pregnene-lGa,170:,21-t1'i0l-3 ,20-dione triacetate, which was dehydrogenated to 6a-flUOITO-A -PIEgHadiEI16-1601,17cg2ltriol-3,20-dione triacetate.

Example V In accordance with the methods of Examples III and IV, there were treated with dry hydrogen chloride 6 8- fluoro 3 ethylenedioxy-pregnane 5a,16a,17a triol- 20-one l6,l7-di'acetate and 6,8-fluoro-3-ethylenedioxyregnane-Sa,16,17a,2l-tetrol-3,20-dione triacetate, respectively. Since this reaction involves the hydrolysis of the ketal group, there were thus directly obtained the respective A 3- ketones.

Example VI A solution Was prepared of 5 g. of A -pregnene-16a, 17a-diol-3,20-dione diacetate in 35 cc. of anhydrous dioxane and then 5 cc. of ethyl orthoformate and 150 mg.

of p-toluenesulfonic acid were added. The mixture was stirred for 30 minutes and then 12 cc. of pyridine and 500 cc. of water were slowly added under stirring and cooling. The mixture was kept at low temperature until the precipitate became crystalline, which was collected by filtration, washed with water, dried and recrystallized from methanol. There was thus obtained 3-ethoxy-A pregnadiene-l6a,17a-diol-20-one diacetate.

A mixture of 4 .g. of the above enol-ether, 2.1 g. of anhydrous sodium acetate and cc. of acetone was cooled to 0 C. and mixed with 3.7 g. or 'N-chlorosuccinimide and 2 cc. of glacial acetic acid. The mixture was stirred for 3 hours at 05 C., ice water was added and the mixture was kept overnight at a temperature around 0 C. The precipitate was collected, washed with water, dried and recrystallized from acetone-hexane. There was thus obtained fifl-chloro-A -pregnene-l6a-l7adiol-3,20-dione diacetate.

By the method described in Example III, the above compound was dehydrogenated by refluxing with selenium dioxide, thus giving 6B-chloro-A -pregnadiene-16a,l7adiol-3,20-dione diacetate.

Example VII The method of the previous example was applied to A -pregnene-l6a,17a,21-triol-3,20-dione triacetate; via the enol-ethyl-ether there was obtained 6,3-chloro-A pregneneal6a,17a,2l-triol-3,20-dione triacetate and then 6 3- chloro A pregnadiene 16u,l7a,2l triol 3,20- dione triacetate.

Example VIII By treatment with dry hydrogen chloride, as has been described for this reaction in Example III, there was inverted the steric configuration at C6 of the 6 8-chloro compounds mentioned in Examples VI and VII.

Example IX The methods described in the previous examples were applied to the diesters of A -pregnene-l6a,l7a-diol-3,20- dione and to the triesters of A -tpregnene-l6a,17a,21-trio1- 3,20-dione, described in Preparations l to 5 inclusive, to obtain the corresponding este-rified intermediate compounds and final products.

Example X A solution of 78 g. of 16a,l7a-oxido-A -pregnene-3p, 2l-diol-20-one ZI-acetate in 2 lt. of glacial acetic acid was treated with 400 cc. of an aqueous solution of chromous chloride prepared by zinc-amalgam reduction of 133 g. of CrCl .6H O. The mixture was kept for 5 minutes at room temperature and the reaction product was precipitated by dilution with water, collected by filtration, washed and re-dissolved in 1.5 lt. of acetone. 10 cc. of concentrated hydrochloric acid was added and the mixture was refluxed for 1 hour and concentrated until crystallization started. The mixture was cooled and the precipitate of the crystalline A -pregnadiene-3fi,21-dio1-2O- one 2l-acetate was collected, washed with water, dried and recrystallized from acetone; M.P. 177-179 C.; [04] 4l (chloroform); max. 242 my, log E 3.93.

A solution of 40 g. of the above compound in 1.2 lt. of acetone containing 8 cc. of acetic acid was cooled to 0 C. and treated with a solution of 18 g. of potassium permanganate in a mixture of cc. of water and 850 cc. of acetone; the mixture was stirred at 0 C. for 5 minutes and filtered through celite; the filtrate was concentrated under reduced pressure, precipitated by dilution with water and the product was collected by filtration. By recrystallization from aqueous acetone there was ob tained A -pregnene-3fl,l6a,l7a,21-tetro l-20-one 21-acetate.

A solution of 13.5 g. of the above compound in 350 cc. of acetone was treated with 3.5 cc. of 72% perchloric acid and stirred for 1 hour at room temperature. There was then added 5% aqueous sodium bicarbonate solution until complete precipitation of the reaction product l. l which was collected, Washed with water, dried and recrystallized from acetone, thus yielding 16u,l7a-isopropylidenedioxy 21 ace'toxy A pregnene 3 B ol 20- one, M.P. 215-216 C.; +8 (chloroform).

A solution of 10 g. of the above acetonide in 100 cc. of chloroform was mixed with an ether solution of monoperphthalio acid containing 1.4 equivalents of reagent and the mixture was kept overnight at room temperature and in the dark. After diluting with water the organic layer was separated, washed with aqueous sodium bicarbonate solution and water, dried over anhydrous sodium sulfate, filtered and evaporated to dryness. Crystallization or the residue from acetone-hexane afiorded l60c,17zxisopropylidenedioxy 21 acetoxy 5 11,60; oxido pregnane-Bfi-ol-ZO-one; M.P. 195-196 C.; [od i0 (chloroform).

A solution of g. of the above compound in 1 1t. of a mixture of equal parts of benzene and ether was treated with cc. of recently distilled boron trifiuoride ethera-te; the mixture was kept overnight at room temperature and diluted with water; the organic layer was separated, washed with water, dried over anhydrous sodium sulfate and the solvent was evaporated under reduced pressure. The residue was purified by chromatography on neutral alumina followed by recrystallization from *acetonehexane, thus furnishing 6fi-fiuoro-16a,17a-isopropylidenedioxy-pregnane 313,5a,21 triol 20 one 21-acetate; M.P. 224-226 C.; [oc] +29.5 chloroform).

.A solution of 2.9 g. of the above compound in 100 cc. of acetone was cooled to 0 C. and was treated under an atmosphere of nitrogen and under continuous stirring with an 8' N solution of chromic acid prepared in dilute sulfuric acid, while the temperature of the mixture was maintained around 0 C., until the brown-red color of chromium trioxide persisted in the mixture. The stirring was continued for 5 minutes more at 0 C. and the mixture was then poured into water and the precipitate formed was collected, washed with water, dried and recrystallized from acetone-hexane, thus producing 6,6- fluoro-16a,17a-isopropylidenedioxy pregnane-5a,21-diol- 3,20-dione 2l-acetate, M.P. 2'25227 C.; [a] +48 (chloroform) A slow stream of dry hydrogen chloride was introduced [for 3 hours into a solution of 1.5 g. of the above compound in 150 cc. of acetone, maintaining the temperature around 0 C. The mixture was poured into ice cold 5% aqueous sodium bicarbonate solution and the prod- :uct was extracted with ethyl acetate, washed With water, dried over anhydrous sodhium sulfate and the solvent was evaporated; recrystallization of the residue from acetone yielded 6a-fluoro-16a,17a-isopropy1idenedioxy- A -pregnane-21-ol-3,20-dione 21-acetate; M.P. 295296 C.; [ab-{406 (chloroform); Amax. 236 my, log E 4.19.

A mixture of 1 g. of the above compound and 100 cc. of 60% formic acid was refluxed for half an hour, cooled, diluted with 200 cc. of ice water and the precipitate was collected, washed with Water, dried and recrystallized from aqueous acetone, thus furnishing 6a-fiuoro-A -pregnene-16a,17o,21-triol-3,20-dione 21-acetate; M.P. 206- 208 C; [a] +86 (chloroform).

' A mixture of 450 mg. of the above compound and 5 cc.

7 of a 1% methanolic solution of potassium hydroxide was stirred [for 1 hour at 0 C. under an atmosphere of nitrogen; after acidifying with a few drops of acetic acid the solvent was removed under vacuum and the residue crystallized from acetone, thus yielding the free 6a-fluoro- A -pregnene-16a,17u,21-triol-3,20-dione.

Example XI A mixture of 5 g. of 6ot-fluoro-16a,17a-isopropylidenedioxy-21-acetoxy-A -pregnene-3,20-dione, 1 g. of selenium V dioxide and 100 cc. of t-butanol was refluxed for 48 12 ing its acetone solution with charcoal and the product was purified by chromatography on neutral alumina. There was thus obtained 6a-fluoro-16a,17a-isopropylidenedioxy-Zl-acetoxy-A -pregnadiene-3,20-dione.

By refluxing the above compound with 60% formic acid, in accordance with the method of Example X, there was obtained 6a-fluoro-n -vpregnadiene-16a,17a,21-triol- 3,20-dione 21-acetate, and then the free alcohol was obtained by treatment with potassium hydroxide.

Example XII In accordance with the method of the previous example, there was dehydrogenated 6a-fiuoro-A -pregnene- 16a,l7a,2l-triol-3,20-dione 21-acetate, intermediate in Example X, to produce 16a,l7a,2l-triol-3,20-di0ne 21-acetate.

Example XIII A mixture of 1 g. of 6ot-fluoro-A -pregnene-1 60:,l7ot,21- triol-3,20-dione 21 acetate, intermediate in Example X, 1 cc. of acetic anhydride and 5 cc. of pyridine was kept overnight at room temperature and poured into water; the precipitate was collected, washed with water, dried and recrystallized from acetone-hexane, thus giving 6afluoro-M-pregnene-l6a,17a,21-triol-3,20 dione 16,21-diacetate. The latter was subjected to the reaction with selenium dioxide in accordance with the method described in Example XI, to produce 6oc-fluoro-A -pregnadienel6oz,l7oc,2l-tfi0l-3,20-'diOne 16,21-diacetate; upon subsequent treatment with dilute methanolic potassium. hydroxide, in accordance with the method of Example X, there was then obtained the free OL-fl OIO-A -PI'BgI1adlCHC- 16oz,l7a,2l-tri0l-3,20-Cli0l16.

A solution of 500 mg. of the above compound in 5 cc. of pyridine was treated with 2 cc. of propionic anhydride and the mixture was kept overnight at room temperature; it was then poured into water, heated for half an hour on the steam bath, cooled and the precipitate was collected, washed with water, dried and recrystallized from acetone-hexane. There was thus obtained Get-fluoro- A -pregnad-iene-16oc,1 7a,21-triol-3,20-dione 16,21-dipr0- pionate.

Example XIV There were mixed 425 cc. of 1.74% dipotassium hydrogen phosphate solution with cc. of 1.38% sodium dihydrogen phosphate (A); a mixture of 1 lt. \of 4.5% sodium chloride solution, 40 cc. of 5.75% potassium chloride solution and 10 cc. of 19.1% magnesium sulfate solution was diluted to 5 lt. (B); there was dissolved 20.9 g. fumaric acid and 14.4 g. of sodium hydroxide in 1 lt. of water and diluted to 1.2 lt. (C); there were then mixed 475 cc. of A, 4.32 lt. of B and 1.2 lt. of C.

The adrenal glands of recently slaughtered bovine were defatted and ground in a meat grinder; 3 kg. of the resulting mass was added to 6 lt. of the above aqueous medium.

There was then added a solution of 3 g. of 6a-fluoro- M-pregnene-l6a,17a,21-triol-3,20-di0ne in the minimum amount of propyleneglycol and the mixture Was stirred for 3 hours at 2837 'C.; 40 lt. of acetone was added and the mixture was stirred for 1 hour further at room temperature. A

The solid was removed by filtration and washed with 2 portions of 10 lt. of acetone, the filtrate and washings were combined and concentrated to 5 lt. under reduced pressure and taking care that the temperature did not rise over 30 C.; the residue was Washed with 3 portions of 4 lt. of hexane and the hexane was discarded. The reaction product was extracted with several portions of V methylene chloride and the extract was washed with water, dried over anhydrous sodium sulfate and conperature.

a column charged with a .ixture of 90 g. of celite and 90 g. of silica gel and the column was washed with a mixture of 3 it. of methylene chloride and 100 cc. of acetone and then with a mixture of 1600 cc. of methylene chloride and 400 cc. of acetone which eluted the 6:1.- fluoro-16a-hydroxy-hydrocortisone; it was then purified by crystallization from acetone-hexane.

Example XV A culture of Cunninghamella bainz'eri ATCC 9244 was prepared by inoculating an aqueous medium containing 2% of peptone and 5% of corn syrup with a vegetating growing culture of such fungus prepared in the same medium and then incubating at 28 C. for 24 hours.

To each lt. of this culture there was added 30 cc. of a 1% solution of 6afluoro-A -pregnadiene-16a,170:,21- triol-3,20-dione in methanol and the mixture Was stirred under aeration at 28 C. for 24 hours. A total of 3 g. of the steroid was incubated in this manner. The product was extracted with several portions of methylene chloride and the extract was washed with water, dried over anhydrous sodium sulfate and concentrated to a small volume under reduced pressure.

The total combined extracts were absorbed on a column prepared with a mixture of 60 g. or celite and 60 g. of silica gel previously washed with methylene chloride. The product was then eluted from the column with a mixture of methylene chloride and acetone 80:20, the solvent was evaporated and the residue crystallized from acetone-methylene chloride. There was thus obtained 6a-fluoro-16a-hydroxy-prednisolone.

Example XVI By essentially following the procedure described in the previous example, but substituting the culture of Cunningharnella by a culture of RhizOptls nigricans ATCC 6227b, there was obtained 6u-fluoro-16a-hydroxy-1l-epiprednisolone.

Example XVII A mixture of 1 g. of 6ot-fl11OIO-l6oc,17ct-iSOPIOPYlidBI1C- dioxy A pregnen-21-ol-3,20dione 21-acetate, intermediate in Example X, and 10 cc. of 1% methanolic potassium hydroxide was stirred for 1 hour at 0 C. and under an atmosphere of nitrogen. The mixture was diluted with water and the precipitate was collected by filtration, washed with water, dried and recrystallized from acetonehexane, thus affording the free 6u-fiuoro-16a,17a-isopropylidenedioxy-n -pregnen-21-ol-3,20-dione.

500 mg. of the above compound was incubated with a culture of the fungus Cunnz'nghamella bainieri ATCC 9244, essentially following the method of incubation described in Example XV, thus producing the acetonide of 6a-fluoro-1 6a-hy-droxy-hydrocortisone.

We claim:

1. The 16,17,21-triesters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6u-fluoro-A -pregnene- 16oz,l7a,21-triol-3,20-dione.

2. The 16,17,2l-triesters of hydrocarbon car-boxylic acids of up to 12 carbon atoms of fi-fiuoro-n -pregnene- 16a,17a,21tri01-3,20-di0ne.

3. The 16,17,21-triesters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6a-chloro-A -pregnene- 16a,17a,21-triol-3,20-dione.

4. The 16,17,21-triesters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6/3-chloro-M-pregnene- 16a,17u,21-triol-3,20-dione.

5. The 16,17,21-triesters of hydrocarbon carboxylic acids of up to 12 carbon atoms or" 6a-fluoro-A -pregnadiene-l6a,17a,2l-triol-3,20-dione.

6. The 16,17,21-triesters of hydrocanbon carboxylic acids of up to 12 carbon atoms of 6fl-fluoro-A pregnadime-16a,17a,21-triol-3,20-dione.

7. The 16,17,21-triesters of hydrocanbon carboxylic acids of up to 12 carbon atoms of 6a-chloro-A -pregnadiene-16a,17a,21-triol-3.20 lione.

8. The 16,17,21-triesters of hydrocarbon carboxylic acids of up to 12 carbon atoms of fi-chloro-n pregiadiene-16a,17a,21-triol-3,20-dione.

10. 6oc-fltl0l0 A pregnadiene-16a,17a,21-triol-3,20- dione.

11. The 21-esters of hydrocarbon carboxylic acids of up to 12 carbon atoms of -fiuoro- A -pregnen 1604, 17 a,2 1-trio1-3,20-dione.

12. The 2'1-esters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6a-fiuoro-A -pregnadiene- 16cc,l7a,21-UiOl-3,20-di0118.

13. The 16,21-diesters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6a fluoro -A -pregnene- 16a,17a,21-triol-3,20-dione.

14. The 16,21-diesters of hydrocarbon canboxylic acids of up to 12 carbon atoms of 6a-fluoro-A -pregpadiene- 16a,17a,21-triol-3,20-dione.

15. A compound of the following formula:

CH2OR wherein R is selected from the group consisting of hydrogen and an acyl group of a hydrocarbon carboxylic acid of up to 12 carbon atoms; R and R are selected from the group consisting of hydrogen and lower alkyl; Y is selected from the group consisting of a double bond between C-1 and C2 and a saturated linkage between 0-1 and C-2; and X is selected from the group consisting of chlorine and fluorine.

16. The 16,17-acetonide of 6a fluoro A pregnene- 16a,17a,21-triol-3,20-dione.

17. The 16,17-acetonide of 6u-fluoro-A -pregnadiene- 16a,17a,21-triol-3,20-dione.

18. The 21-esters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6u-fluorc-16a,17a-isopropylideuedioxy-N-pregnen-Z 1-ol-3,20-dione.

19. The 21-esters of hydrocarbon carboxylic acids of up to 12 carbon atoms of 6a-fluoro-16a-isopropylidene dioxy-A -pregnadien-21-ol-3,20-dione.

No references cited.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 107 240 October 15, 1963 Howard J. Ringold et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 14, line 61, for "l6 1is0pr0pylidene-" read Signed and sealed this 14th day of April 1964.

(SEAL) Attest: EDWARD J BRENNER ERNEST W. SWIDER Attesting Officer Commissioner of Patents 

1. THE 16,17,21-TRIESTERS OF HYDROCARBON CARBOXYLIC ACIDS OF UP TO 12 CARBON ATOMS OF 6A-FLUORO$4-PREGNENE16A,17A,21-TRIOL-3,20-DIONE.
 15. A COMPOUND OF THE FOLLOWING FORMULA: 